[Patch, fortran] PR109451 - ICE in gfc_conv_expr_descriptor with ASSOCIATE and substrings

2023-04-12 Thread Paul Richard Thomas via Fortran
Hi All,

I think that the changelog says it all. OK for mainline?

Paul

Fortran: Fix some deferred character problems in associate [PR109451]

2023-04-07  Paul Thomas  

gcc/fortran
PR fortran/109451
* trans-array.cc (gfc_conv_expr_descriptor): Guard expression
character length backend decl before using it. Suppress the
assignment if lhs equals rhs.
* trans-io.cc (gfc_trans_transfer): Scalarize transfer of
associate variables pointing to a variable. Add comment.


gcc/testsuite/
PR fortran/109451
* gfortran.dg/associate_61.f90 : New test
diff --git a/gcc/fortran/trans-array.cc b/gcc/fortran/trans-array.cc
index e1725808033..3d90a02cdac 100644
--- a/gcc/fortran/trans-array.cc
+++ b/gcc/fortran/trans-array.cc
@@ -7934,8 +7934,12 @@ gfc_conv_expr_descriptor (gfc_se *se, gfc_expr *expr)
 	  else
 	tmp = se->string_length;
 
-	  if (expr->ts.deferred && VAR_P (expr->ts.u.cl->backend_decl))
-	gfc_add_modify (&se->pre, expr->ts.u.cl->backend_decl, tmp);
+	  if (expr->ts.deferred && expr->ts.u.cl->backend_decl
+	  && VAR_P (expr->ts.u.cl->backend_decl))
+	{
+	  if (expr->ts.u.cl->backend_decl != tmp)
+	gfc_add_modify (&se->pre, expr->ts.u.cl->backend_decl, tmp);
+	}
 	  else
 	expr->ts.u.cl->backend_decl = tmp;
 	}
diff --git a/gcc/fortran/trans-io.cc b/gcc/fortran/trans-io.cc
index 9b54d2f0d31..67658769b9e 100644
--- a/gcc/fortran/trans-io.cc
+++ b/gcc/fortran/trans-io.cc
@@ -2620,9 +2620,13 @@ gfc_trans_transfer (gfc_code * code)
 	  gcc_assert (ref && ref->type == REF_ARRAY);
 	}
 
+  /* These expressions don't always have the dtype element length set
+	 correctly, rendering them useless for array transfer.  */
   if (expr->ts.type != BT_CLASS
 	 && expr->expr_type == EXPR_VARIABLE
 	 && ((expr->symtree->n.sym->ts.type == BT_DERIVED && expr->ts.deferred)
+	 || (expr->symtree->n.sym->assoc
+		 && expr->symtree->n.sym->assoc->variable)
 	 || gfc_expr_attr (expr).pointer))
 	goto scalarize;
 
! { dg-do run }
! Test fixes for PR109451
! Contributed by Harald Anlauf  
!
  call dcs3(['abcd','efgh'])
contains
  subroutine dcs3(a)
character(len=*), intent(in)  :: a(:)
character(:), allocatable :: b(:)
b = a(:)
call test (b, a, 1)
associate (q => b(:))! no ICE but print repeated first element
  call test (q, a, 2)
  print *, q
end associate
associate (q => b(:)(:)) ! ICE
  call test (q, a, 3)
  associate (r => q(:)(1:3))
call test (r, a(:)(1:3), 4)
  end associate
end associate
associate (q => b(:)(2:3))
  call test (q, a(:)(2:3), 5)
end associate
  end subroutine dcs3
  subroutine test (x, y, i)
character(len=*), intent(in) :: x(:), y(:)
integer, intent(in) :: i
if (any (x .ne. y)) stop i
  end subroutine test
end
! { dg-output " abcdefgh" }


Re: [Patch, fortran] PR109451 - ICE in gfc_conv_expr_descriptor with ASSOCIATE and substrings

2023-04-12 Thread Harald Anlauf via Fortran

Hi Paul,

On 4/12/23 17:25, Paul Richard Thomas via Gcc-patches wrote:

Hi All,

I think that the changelog says it all. OK for mainline?


this looks almost fine, but still fails if one directly uses the
dummy argument as the ASSOCIATE target, as in:

program p
  implicit none
  character(4) :: c(2) = ["abcd","efgh"]
  call dcs0 (c)
! call dcs0 (["abcd","efgh"])
contains
  subroutine dcs0(a)
character(len=*), intent(in) :: a(:)
print *, size(a),len(a)
associate (q => a(:))
  print *, size(q),len(q)
end associate
associate (q => a(:)(:))
  print *, size(q),len(q)
end associate
return
  end subroutine dcs0
end

This prints e.g.

   2   4
   2   0
   2   0

(sometimes I also get junk values for the character length).

Can you please have another look?

Thanks,
Harald



Paul

Fortran: Fix some deferred character problems in associate [PR109451]

2023-04-07  Paul Thomas  

gcc/fortran
PR fortran/109451
* trans-array.cc (gfc_conv_expr_descriptor): Guard expression
character length backend decl before using it. Suppress the
assignment if lhs equals rhs.
* trans-io.cc (gfc_trans_transfer): Scalarize transfer of
associate variables pointing to a variable. Add comment.


gcc/testsuite/
PR fortran/109451
* gfortran.dg/associate_61.f90 : New test




Re: [Patch, fortran] PR109451 - ICE in gfc_conv_expr_descriptor with ASSOCIATE and substrings

2023-04-12 Thread Paul Richard Thomas via Fortran
Hi Harald,

That's interesting - the string length '.q' is not set for either of the
associate blocks. I'm onto it.

Thanks

Paul


On Wed, 12 Apr 2023 at 20:26, Harald Anlauf  wrote:

> Hi Paul,
>
> On 4/12/23 17:25, Paul Richard Thomas via Gcc-patches wrote:
> > Hi All,
> >
> > I think that the changelog says it all. OK for mainline?
>
> this looks almost fine, but still fails if one directly uses the
> dummy argument as the ASSOCIATE target, as in:
>
> program p
>implicit none
>character(4) :: c(2) = ["abcd","efgh"]
>call dcs0 (c)
> ! call dcs0 (["abcd","efgh"])
> contains
>subroutine dcs0(a)
>  character(len=*), intent(in) :: a(:)
>  print *, size(a),len(a)
>  associate (q => a(:))
>print *, size(q),len(q)
>  end associate
>  associate (q => a(:)(:))
>print *, size(q),len(q)
>  end associate
>  return
>end subroutine dcs0
> end
>
> This prints e.g.
>
> 2   4
> 2   0
> 2   0
>
> (sometimes I also get junk values for the character length).
>
> Can you please have another look?
>
> Thanks,
> Harald
>
>
> > Paul
> >
> > Fortran: Fix some deferred character problems in associate [PR109451]
> >
> > 2023-04-07  Paul Thomas  
> >
> > gcc/fortran
> > PR fortran/109451
> > * trans-array.cc (gfc_conv_expr_descriptor): Guard expression
> > character length backend decl before using it. Suppress the
> > assignment if lhs equals rhs.
> > * trans-io.cc (gfc_trans_transfer): Scalarize transfer of
> > associate variables pointing to a variable. Add comment.
> >
> >
> > gcc/testsuite/
> > PR fortran/109451
> > * gfortran.dg/associate_61.f90 : New test
>
>

-- 
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